Jack Johnson's Kokua Festival returns this year with a lineup that includes Ziggy Marley and Taj Mahal.

After taking a break in '09, the sixth Kokua Festival will take place April 23 and 24 at the Waikiki Shell.

In addition to full-band performances by Johnson and Mahal, and a solo acoustic set by Marley, two local acts—Jake Shimabukuro and Anuhea—will round out the concert bill.

Tickets for Hawaii residents only will go on sale Feb. 20 at all Ticketmaster outlets, online at http://www.ticketmaster.com or by phone at (800) 745-3000. Tickets for the out-of-state general public will go on sale the following day, Sunday the 21st, also through Ticketmaster.

On Feb. 13, listeners to STAR 101.9 will be offered pre-sale opportunities by participating in beach cleanups around Oahu and on Maui. Visit http://www.star1019.com for more details on cleanup locations and times.

More than 50 green-themed booths will also be gathered together on the Waikiki Shell grounds during the festival.

All proceeds from the festival go to the nonprofit Kokua Hawaii Foundation, founded by Jack and his wife, Kim Johnson, to support environmental education programs in the state's schools and communities, specifically to further support school recycling on Oahu, sponsor field trips and support the farm-to-school program 'AINA in Schools.

The foundation has also expanded its community outreach with its Simplify the Holidays campaign and the new Plastic Free Hawaii coalition.

Johnson's sixth studio album will be released on June 1. Johnson is familiar with his festival guests, as he provided guest vocals to both Marley's and Mahal's latest albums.